tty: iuu_phoenix: fix locking.

Bring in the relevant bits of the 0.9 vendor driver.

Signed-off-by: Olivier Bornet <Olivier.Bornet@puck.ch>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 13 insertions, 16 deletions

diff --git a/drivers/usb/serial/iuu_phoenix.c b/drivers/usb/serial/iuu_phoenix.c
index bb572cee6ecd..637d0ddbfb42 100644
--- a/drivers/usb/serial/iuu_phoenix.c
+++ b/drivers/usb/serial/iuu_phoenix.c
@@ -650,32 +650,33 @@ static int iuu_bulk_write(struct usb_serial_port *port)
         unsigned long flags;
         int result;
         int i;
+        int buf_len;
         char *buf_ptr = port->write_urb->transfer_buffer;
         dbg("%s - enter", __func__);
 
+        spin_lock_irqsave(&priv->lock, flags);
         *buf_ptr++ = IUU_UART_ESC;
         *buf_ptr++ = IUU_UART_TX;
         *buf_ptr++ = priv->writelen;
 
-        memcpy(buf_ptr, priv->writebuf,
-               priv->writelen);
+        memcpy(buf_ptr, priv->writebuf, priv->writelen);
+        buf_len = priv->writelen;
+        priv->writelen = 0;
+        spin_unlock_irqrestore(&priv->lock, flags);
         if (debug == 1) {
-                for (i = 0; i < priv->writelen; i++)
+                for (i = 0; i < buf_len; i++)
                         sprintf(priv->dbgbuf + i*2 ,
                                 "%02X", priv->writebuf[i]);
-                priv->dbgbuf[priv->writelen+i*2] = 0;
+                priv->dbgbuf[buf_len+i*2] = 0;
                 dbg("%s - writing %i chars : %s", __func__,
-                    priv->writelen, priv->dbgbuf);
+                    buf_len, priv->dbgbuf);
         }
         usb_fill_bulk_urb(port->write_urb, port->serial->dev,
                           usb_sndbulkpipe(port->serial->dev,
                                           port->bulk_out_endpointAddress),
-                          port->write_urb->transfer_buffer, priv->writelen + 3,
+                          port->write_urb->transfer_buffer, buf_len + 3,
                           iuu_rxcmd, port);
         result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
-        spin_lock_irqsave(&priv->lock, flags);
-        priv->writelen = 0;
-        spin_unlock_irqrestore(&priv->lock, flags);
         usb_serial_port_softint(port);
         return result;
 }
@@ -769,14 +770,10 @@ static int iuu_uart_write(struct tty_struct *tty, struct usb_serial_port *port,
                 return -ENOMEM;
 
         spin_lock_irqsave(&priv->lock, flags);
-        if (priv->writelen > 0) {
-                /* buffer already filled but not commited */
-                spin_unlock_irqrestore(&priv->lock, flags);
-                return 0;
-        }
+
         /* fill the buffer */
-        memcpy(priv->writebuf, buf, count);
-        priv->writelen = count;
+        memcpy(priv->writebuf + priv->writelen, buf, count);
+        priv->writelen += count;
         spin_unlock_irqrestore(&priv->lock, flags);
 
         return count;